1. Field of the Invention
The present invention relates to an image processing apparatus and method. In particular, the present invention relates to an image processing apparatus and so on, which performs image synthesis by texture-mapping an image according to image data onto a computer graphics image.
2. Description of the Related Art
In a three-dimensional graphics system, drawing of a whole image is performed by decomposing three-dimensional coordinates into polygons such as triangles or the like and drawing the polygons. Accordingly, in this case, the three-dimensional image may be defined as a combination of polygons. However, surfaces of surrounding objects may have repeated patterns of complicated shapes in many cases, and as the shape or pattern of an object becomes complicated and elaborated, it becomes difficult to perform modeling of the corresponding shape or pattern into triangles or the like. As a means for solving this, texture mapping has been used.
The texture mapping realizes a high-reality image with a small number of vertexes by attaching image data received from a scanner or the like to the surface of an object, and defines mapping from an object coordinate system onto a texture coordinate system. The texture mapping obtains mapping from a window coordinate system onto a texture coordinate system, and obtains texture cell elements (texels) which are texture elements corresponding to respective picture cell elements (pixels) in the window coordinate system.
Image data that is used for texture is stored in a memory region that is called a texture memory. Accordingly, by performing updating of the texture memory as necessary by using moving image data, texture mapping processing with moving images becomes possible.
For example, in Japanese Unexamined Patent Application Publication No. 2002-369076, a three-dimensional special effects device is described, which transits a certain texture mapped image of three-dimensional computer graphics (CG) to another image with the lapse of time through the control of texture coordinates.
Also, for example, in Japanese Unexamined Patent Application Publication No. 2000-152079, a method of generating a series of images is described, as technology of synthesizing computer graphics and real images, which designates a region or correspondence between a playback start time of an image to be texture-mapped and a frame, and realizes desired frame attachment on a time axis.
Also, for example, in Japanese Unexamined Patent Application Publication No. 2001-014489, a drawing apparatus is described, which realizes seamless shift control of a texture mapping state of a moving image of 3D CG and the display of a moving image only.